• Asian-Australasian Journal of Animal Sciences
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• 제31권4호
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• pp.529-536
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• 2018

Objective: Fresh sugarcane has been a new roughage source for ruminant's in semiarid regions, a function of the decline of sugar and alcohol industry in recent years. However, there is little data published regarding lambs fed sugarcane associated with spineless cactus. This study evaluated the effect of sugarcane replacement with spineless cactus (0%, 33%, 66%, and 100%) in the diet of Santa $In\hat{e}s$ lambs on carcass characteristics. Methods: Thirty-six non-castrated Santa Ines lambs at four months of age and an initial body weight of $22{\pm}2.3kg$ were assigned in a randomized block design and slaughtered after 70 days of confinement. The effects of spineless cactus as a replacement for sugarcane in the diet of the lambs on the carcass characteristics, commercial cut weight and yield, leg tissue composition, and carcass measurements were studied. Results: The study revealed quadratic behavior in slaughter body weight, and hot and cold carcass weight, with maximum values of 38.60, 18.60, and 18.11 kg and replacement levels of 40.18%, 44.42%, and 43.14%, respectively. The cold carcass yield presented an increasing linear behavior. The compactness index of carcass and leg presented a quadratic effect, with estimated maximal values of 0.28 and 0.57 kg/cm and replacement levels of 43.37% and 45.5%, respectively. The weights of commercial cuts of leg, loin, shoulder, and breast showed quadratic behavior, with maximum values of 2.79, 0.852, 1.46, and 1.30 kg and replacement levels of 49.5, 45.32, 39.0, and 40.7, respectively. For tissue composition, quadratic behavior was verified for leg weight, subcutaneous fat, and total fat. Conclusion: The replacement of sugarcane by spineless cactus at level 44% is recommended for finishing lambs considering that this level improved most of the carcass characteristics, weights, and yields of commercial cuts and leg tissue composition.

• 한국식품과학회지
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• 제29권3호
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• pp.509-515
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• 1997

식품공업과 의학, 의료, 화장품 등 많은 분야에서 널리 이용되고 있는 단백질 분해 효소의 하나인 papain을 papaya 유액으로부터 추출해내기 위한 최적 조건을 반응표면 분석법(RSM)을 이용하여 결정하였다. 중심 합성법에 의한 실험 계획을 설정하여 부분요인 실험법에 의하여 crude papain을 추출 및 분리하고 선정된 독립 인자의 반응 표면에 대한 영향을 분석하여 다중 회귀 분석으로 다음과 같은 모델식(Y)을 얻었으며, EDTA는 다중 회귀 분석에 의하여 제거되었다. $Y=29.0630-2.5812X_3+149.3208X_4+{13.1705X_1}^{2}+{0.0208X_3}^2-{9.8494X_4}^2$. 따라서 이 결과 papain 추출은 $NaHSO_3$, 농도가 4%, 추출 시간은 120분, pH는 7.6일때 최적 조건이 된다. 이러한 최적 추출 조건으로 얻은 효소 단백질 추출 양의 실험치는 793.16 mg prot./g latex로, 이는 효소 단백질 추출 예측치인 795.60 mg prot./g latex와 매우 근접한 값을 나타냄으로써 r=0.9951의 높은 상관 관계를 입증하였다.

• 한국산림과학회지
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• 제90권2호
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• pp.176-183
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• 2001

본(本) 연구(硏究)에서는 목재(木材)의 다목적(多目的) 생산량(生産量)(multiple-product yield) 예측(豫測)에 대한 해결책(解決策)으로서 테다소나무(Pinus taeda L.) 조림지(造林地)를 대상으로 하여 Weibull 직경분포(直徑分布) 수확예측(收穫豫測) 시스템을 개발(開發)하였다. 직경분포(直徑分布) 수확예측(收穫豫測) 모형(模型)을 개발(開發)하기 위하여, 4개의 백분위수(百分位數) 식(式)들을 근거(根據)로 한 모수(母數) 회복(回復)(parameter recovery) 절차법(節次法)을 적용(適用)하였다. 또한 직경급(直徑級)에 대한 수확량(收穫量) 계산(計算)을 위하여 단목(單木) 수고(樹高) 예측식(豫測式)을 개발(開發)하였으며, 그리고 단목(單木) 재적(材積) 예측식(豫測式)을 이용(利用)함으로써 직경급(直徑級)에 대해 기대되는 재적량(材積量)을 계산(計算)할 수가 있다. 본(本) 연구(硏究)에서 사용(使用)된 직경급(直徑級)에 대한 Weibull 누적함수(累積函數)의 상한선(上限線) 차이(差異) 방법(方法)이 기존(旣存)의 상한선(上限線)과 하한선(下限線)의 절차법(節次法)보다도 괄약오차(括約誤差)를 줄 일수 있는 보다 나은 절차법(節次法)이였다. 본(本) 연구(硏究)에서 제시(提示)된 Weibull 직경분포(直徑分布) 수적예측(收積豫測) 시스템에 대한 타당성(妥當性) 검정(檢定)의 한 방법(方法)으로서 Kolmogorov-Smirnov test 결과(結果), 각(各) plot당 예측(豫測)된 직경분포(直徑分布)와 관측(觀測)된 직경(直徑) 분포급(分布級) 사이에서 통계적(統計的) 유의성(有意性)이 없는 것으로 나타났다. 이와 같은 직경분포(直徑分布) 수확예측(收穫豫測) 시스템은 다목적(多目的) 목재(木材) 생산량(生産量) 예측(豫測)과 임분(林分) 구조(構造) 모형(模型) 및 임분(林分)의 경영(經營)에 유용(有用)한 정보(情報)를 제공(提供)할 것이다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.301-303
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• 2008

In order to investigate the influence of anisotropy on formability and also to obtain guidelines for the stamping process design in friction stir welded TWB (tailor welded blank), the aluminum ally 6111-T4 sheet was welded with three different types of combination: RD||RD, TD||RD and TD||TD (Here, RD and TD mean the rolling direction and transverse direction, respectively) and then hemisphere dome stretching and cylindrical cup drawing tests were carried out. In addition, the numerical analysis was performed to confirm the validity of experimental results. For the numerical analysis, the non-quadratic orthotropic yield function, Yld2004-18p was utilized to represent precise anisotropic properties.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.58-61
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• 2001

An implicit finite element formulation for axisymmetric tube hydroforming is investigated. In order to describe normal anisotropy of the tube, Hill's non-quadratic yield function is employed. The frictional contact between die and tube and frictionless contact between tube and fluid are considered using the mesh-normal vector computed from finite element mesh of the tube. In order to verify the validity of the developed finite element formulation, the axisymmetric tube bulge test is simulated and simulation results are compared with experimental measurements. In the axisymmetric tube hydroforming process, an optimal hydraulic curve is pursued by performing the simulation with various internal pressures and axial forces.

• 소성∙가공
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• 제11권1호
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• pp.75-83
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• 2002

Recently, the hydroforming process is widely applied to the automotive industry and rapidly spreaded to other industries. In this paper, An implicit finite element formulation for simulating axisymmetric tube hydroforming processes is performed. In order to describe normal anisotropy of the tube, Hill's non-quadratic yield function is employed. The frictional contact between die and tube and the frictionless contact between tube and fluid are considered using the mesh-normal vectors computed from the finite element mesh of the tube. The complete set of the governing relations comprising equilibrium and interfacial equations is linearized for Newton-Raphson procedure. In order to verify the validity of the developed finite element formulation, the axisymmetric tube bulge test is simulated and the simulation results are compared with experimental measurements. In a simulation of stepped circular tube hydroforming processes, an optimal hydraulic pressure curve is pursued by considering simultaneously internal pressures and axial forces.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.75-78
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• 2003

In order to describe the Bauschinger and transient behavior of orthotropic fiber-reinforced composites, a combined isotropic-kinematic hardening law based on the non-linear kinematic hardening rule was considered here, in particular, based on the Chaboche type law. In this modified constitutive law, the anisotropic evolution of the back-stress was properly accounted for. Also, to represent the orthotropy of composite materials, Hill's 1948 quadratic yield function and the orthotropic elasticity constitutive equations were utilized. Furthermore, the numerical formulation to update the stresses was also developed based on the incremental deformation theory for the boundary value problems. Numerical examples confirmed that the new law based on the anisotropic evolution of the back-stress complies well with the constitutive behavior of highly anisotropic materials such as fiber-reinforced composites.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 추계학술대회논문집
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• pp.24-27
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• 1997

In the present work, rigid-plastic continuum elements employing the shape change and anisotropic effects are derived for the purpose of applying more realistic blankholding force condition in three-dimensional finite element analysis of sheet metal forming process. In order to incorporate the effect of shape change effectively in the derivation of finite element equation using continuum element for sheet metal forming, the convected coordinate system is introduced, rendering the analysis more rigorous and accurate. The formulation is extended to cover the orthotropic material using Hill's quadratic yield function. For the purpose of applying more realistic blankholding force condition, distributed normal and associated frictional tangent forces are employed in the blankholder, which is pressed normal and associated frictional tangent forces are employed in the blankholder, which is pressed against the flange until the resultant contact force with the blank reaches the prescribed value. As an example of sheet metal forming process coupling the effect of planar anisotropy and that of blankholding boundary condition, circular cup deep drawing has been analyzed considering both effects together.

• 소성∙가공
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• 제26권3호
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• pp.144-149
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• 2017

In order to characterize the macroscopic mechanical response of ultra-thin (0.1 mm thick) ferritic stainless steel sheet at various loading paths, a crystal plasticity finite element method (CP-FEM) was introduced. The accuracy of the prediction results was validated by comparing with the experimental data. Based on the results, the forming limit diagram (FLD) was predicted using a modified Marchinicak-Kuczinski model coupled to a non-quadratic anisotropic yield function, namely, Yld2000-2d. The predicted FLD was found to be in good agreement with the experimental data.

• 원예과학기술지
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• 제32권2호
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• pp.165-170
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• 2014

본 연구는 완전제어형 식물공장에서 선형 지수 함수를 이용하여 재식거리($15{\times}10$, $15{\times}15$, $15{\times}20$, $15{\times}25$cm)에 따른 씀바귀의 생육과 수량 모델을 개발하고자 수행되었다. 개체당 건물중은 25cm 처리구가 가장 높았으며, 10cm 처리구가 가장 낮았다. 단위면적당 건물중으로 보면 15cm 처리구가 가장 높았으며, 25cm 처리구가 가장 낮았다. 따라서 씀바귀 생육을 위한 적정 재식밀도와 재식거리는 각각 44 plants/$m^2$와 $15{\times}15$cm였다. 정식 후 일수에 따른 건물중의 변화 곡선은 선형 지수적인 형태를 보였으며, 재식거리에 따른 선형 지수 형태를 이용하여 모델식을 예측할 수 있었다. 개체당 건물중과 개체당 생체중과의 관계는 재식거리와는 무관하게 직선적인 관계를 보여, 건물중 예측으로 생체중도 예측할 수 있었다. 선형 지수 함수식에서 작물생장율과 상대생장율, lost time는 쌍곡선 형태를 보였다. 씀바귀의 광사용효율는 $4.3-6.1g{\cdot}MJ^{-1}$였다. 재식거리에 따른 씀바귀의 생육과 수량은 선형 지수 함수식으로 정확하게 예측할 수 있었다. 결론적으로, 선형 지수 함수는 완전제어형 식물 공장에서 씀바귀의 생육과 수량을 예측하는데 유용한 함수였으며, 생육과 수량 모델을 개발할 수 있었다.